Endoscope-type device, especially for emergency intubation

ABSTRACT

The invention relates to an endoscope-type device, particularly an endoscope for emergency intubation, comprising a holding portion ( 7 ) and a shaft ( 1 ) which is configured to be flexible at least in partial areas, with at least two longitudinal bendable pulling and/or pushing elements acting on said shaft ( 1 ) in the axial direction at different distances from the proximal end, with said pulling and/or pushing elements extending as far as the proximal end and being lockably received in a fixing device.

TECHNICAL FIELD OF THE INVENTION

The invention relates to an endoscope-type device having a shaft thatmay be manually shaped and then reasonably fixed in the desired shape.

BACKGROUND

Endoscope-type devices are used in many different fields of application,such as medicine, for example endoscopy, particularly for emergencyintubation, but also in engineering, for example as endoscope-type toolswith an endoscope-type, flexible and formable shaft, and in generalfields of application such as the controlled movement of extremities,particularly human extremities.

Intubation is the introduction of a tube (or a catheter) consisting ofrubber or plastic material into the larynx and then into the trachea ofthe individual. It serves to maintain an effective exchange of gases,which is essential for providing organs with oxygen, among other things,and which is usually effected by respiration. In situations in which thepatient is not capable of breathing himself any more as a result of anillness, an injury or medication, for example when a narcosis is carriedout, artificial respiration has to be carried out. A prerequisite forthis artificial respiration is a secure connection between therespirator and the patient's respiratory tract. In order to ensure thatair is supplied to the respiratory organs only, without any air reachingthe digestive tract via the esophagus, the tube is pushed with itsdistal end into the trachea via the mouth or the nose and is positionedthere in such a way that both lobes of the lung are aerated. At theproximal end, the tube is connected with the tube system of therespirator via a standardized projection (connector).

If the tip of the tube is not positioned in the trachea, the lobes ofthe lung are not aerated. In this case, the blood flowing through thelung is not enriched with oxygen to a sufficient extent, and the organsare not provided with oxygen any more. Depending on how long the organsare not supplied with oxygen to a sufficient extent, apart from thecomplete restoration of all bodily functions, permanent cerebralinjuries (such as a coma) or even death because of cardiac arrest mightbe possible. Faulty intubation, meaning those maneuvers of intubation inwhich the tube is not positioned correctly and the tip of the tube restsin the esophagus instead of the trachea, for example, will have the sameconsequences.

There are several methods and shapes of tubes to ensure securepositioning of the tip of the tube. With patients for whom no specialanatomic or pathological conditions are to be taken into account,intubation is usually easy and fast to carry out with the usual methods,mainly the laryngoscopical intubation. However, difficulties may ariseif there are pathological changes or anatomic peculiarities; in thiscase, the patient, who is not breathing any more, is subjected toartificial respiration by applying a combination of laryngoscopicalintubation and fiber-optical intubation or by using devices employedspecifically for this purpose.

In emergency intubation, which usually means the intubation of a personwho has become unconscious and whose lung is liable to fill with water,it is necessary to supply air from outside as soon as possible in orderto minimize the risk of lung injury.

In an emergency situation, i.e. at the site of the accident and usuallynot in a hospital, this is done by means of laryngoscopical intubation;here, using a laryngoscope, lifting the tongue root and the epiglottis,the patient's pharynx is opened in order to gain a good view on theentrance to the larynx, the rima glottidis. If the rima glottidis isonly partially visible, it is difficult to introduce the tube. Onemanages by changing the shape of the tube in its longitudinal axis untilthe tip of the tube can securely reach the entrance to the trachea. Bynow, this has been done by internally splinting the tube by means of aguide rod in the form of a flexible wire sheathed with plastic materialwhich is inserted therein, which is so stable after bending that ittransfers its shape in the longitudinal axis to the elastic tube. It isdisplaceable in the longitudinal axis within the tube, so it may alsoproject from the distal tube end with its soft tip. Depending on theanatomic conditions, the guide rod is bent in such a way that its tipcan be pushed through the rima glottidis and the tip of the tube canthen be positioned in the trachea by sliding it over the guide rod. Ifthe rima glottidis is not visible because of anatomic difficulties, sothe path of the tube or the guide rod cannot be watched when it ispushed forward, there is a higher risk of injuries and a markedlyreduced hitting accuracy. Although there are special instruments whichare to make it possible to see the rima glottidis even under difficultconditions, the view through the tube is often obstructed when they areused because of the narrow conditions. For this reason, in difficultcases, the application of laryngoscopical intubation is not favorable.

Therefore, in these cases, fiber-optical intubation is preferablyapplied, in which an endoscope of the type mentioned at the beginning isused in order to find the entrance to the trachea and to illuminate andmake visible the area to be inspected. Furthermore, by means of amechanism mounted on the holding portion of the endoscope, the positionof the tip of the endoscope can be changed, and it can therefore bevisibly pushed through the rima glottidis. The tube previously placedupon the tube of the endoscope is then pushed forward as far as into thetrachea; then, the endoscope is pulled out of the tube which has beenpositioned correctly, and the tube is fixed to the patient's head and isconnected with the respirator.

However, the fiber-optical method cannot be carried out optimally in allcases, either. It is particularly different if the patient is lying onhis back and his musculature is slackened, because the tongue root fallsback, thus blocking the path to the trachea. Furthermore, as one hand isrequired to guide the endoscope—usually by means of the surroundingtube—in fiber-optical intubation and a second hand is required tooperate the mechanism of the endoscope, another person is necessary tolift the tongue root by means of a laryngoscope; however, such a personis not necessarily present in case of an emergency.

In the document EP 0 742 026 A, a flexible and simultaneously formableendoscope with a viewing lens was therefore suggested, over which a tubecan be slid. Here, formability and flexibility was to be obtained by anarticulated rod whose individual adjacent links with convex or concavesurfaces could be tensed by tensional or compressive forces. What wasdisadvantageous, however, was that tests during manufacturing revealedthat this principle is very complex because of the frictional forceswhich are difficult to control and that sufficient flexibility withsimultaneously adjustable stiffness cannot be realized with thisendoscope.

SUMMARY OF THE INVENTION

Thus, the object of the invention is to provide an endoscope-type deviceat low cost and in a simple manner, which overcomes the above-mentioneddrawbacks and which comprises, at least partially, a formable and stiffshaft which, after releasing, changes into a flexible condition at leastin these partial areas.

According to the invention, this object is achieved with anendoscope-type device with a fixing device at its proximal end. Byarranging longitudinal bendable pulling and/or pushing elements or theirdistal ends at the shaft at different distances from the proximal end,the shaft can manually be brought into a desired shape in the flexible,i.e. non-fixed condition, which becomes stiff by locking the pullingand/or pushing elements with the fixing device. Here, the pulling and/orpushing elements, which are limited at least in the pushing or pullingdirection, act on the shaft, and the stability of the stiffness can beincreased by a bilateral limitation.

In an embodiment of the invention, the pulling and/or pushing elements,for example steel strands, may be movably received in guide elements atthe shaft in the longitudinal direction. Hereby, the stability of therigidity is advantageously increased, as the path length of the pullingand/or pushing elements is defined exactly by the fact that the guideelements receiving the pulling and/or pushing elements are fixedlypositioned.

In a further embodiment of the invention, seen from a cross-sectionalview, the pulling and/or pushing elements are positioned in aring-shaped arrangement within said shaft (1) at the inner peripherythereof, so their lever action and thus the stability of the rigidity,which increases with increasing distance from the center line, isadvantageously improved.

In a further embodiment of the invention, lateral guide means arearranged inside the shaft which, seen in a cross-sectional view, areopposed to each other, and which are fixedly connected with the shaft atleast in partial areas. Advantageously, this will prevent undesiredbending of the shaft within the plane defined by lateral guide means.

In a further embodiment of the invention, the channel is configured as achannel for an optical light guide and an optical image guide or as achannel for instruments. Advantageously, this makes it possible to checkand facilitate the arrival at an aiming point when the endoscope-typedevice is introduced into a non-visible portion.

In a further embodiment of the invention, pulling and/or pushingelements act on the shaft in pairs in the axial direction, substantiallyat equal distances from the proximal end. Hereby, as a result of thecooperation of pulling and pushing forces of a pair, stability may beincreased. Such pairs of pulling and/or pushing elements may be arrangedpoint-symmetrically at the shaft in order to advantageously exert theoptimum stability in a freely movable shaft without any laterallimitation with their maximum distance from each other.

In case of lateral limitation to the movement, however, it may also beadvantageous for an optimum effect of the forces to arrange pairs ofpulling and/or pushing elements at the shaft to be symmetrical to thehorizontal or the vertical axis, in other words: symmetrical to theplane defined by the lateral guide means, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, the invention is explained in greater detail with theaid of an embodiment shown in the drawings, in which

FIG. 1 shows a longitudinal sectional view of a shaft of anendoscope-type device according to the invention;

FIG. 2 shows a cross-sectional view of the shaft according to FIG. 1;

FIG. 3 shows a perspective, schematic view of the structure of a partialportion of the shaft according to FIG. 1;

FIG. 4 shows a lateral view in partial section of the endoscope-typedevice according to the invention;

FIG. 5 shows a front view of the detail according to FIG. 4.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a shaft 1 of an endoscope-type device according to theinvention with a distal end 3 and a proximal end 5. Adjacent theproximal end 5 of the shaft 1, a housing 6 with a holding portion 7 (seeFIG. 4) and an eyepiece 8 as shown in FIG. 4 is arranged.

As will be apparent from FIG. 3, the shaft 1 consists of a spring with aring-shaped cross-section, particularly a leaf spring 9, which extendsfrom the proximal end 5 to the distal end 3 of the shaft 1. The spring,the ring-shaped cross-section of which includes both the circular shape,the oval shape and the polygonal shape, is made of steel or plasticmaterial, for example.

At the inner periphery or the inner wall of the leaf spring 9,several—for example five—ropes 11 to 11″″ guided on top and five ropes13 to 13″″ guided at the bottom and lateral guide means at the left side15 and the right side 17 are arranged.

The cross-sectional distribution of ropes 11 to 11″″, 13 to 13″″, 15 and17 shown in FIG. 2 illustrates that the lateral guide means arepositioned, when seen from a cross-sectional view, at the innerperiphery of the leaf spring 9 in such a way that they lie opposite toeach other in a horizontal mid-plane or are arranged on a horizontalcenter line H. Above and below the axis H, ropes 11 to 11″″ and 13 to13″″ guided on top and at the bottom are arranged at the innerperiphery, particularly at equal distances.

As will be apparent from FIG. 2, all ropes may be configured as strands,particularly made of steel or plastic material, with five leads, forexample. The ropes 11 to 11″″ and 13 to 13″″ guided on top and at thebottom extend in guide elements 19 which may be configured to bering-shaped and which are arranged at the inner periphery in thelongitudinal direction and along a longitudinal axis in distances,particularly equal distances, corresponding to the turn or theconvolution and the width of the leaf spring, for example by laserwelding.

The ropes 11 to 11″″ and 13 to 13″″, whose outer periphery is ofsomewhat smaller dimension than the inner periphery of the guideelements 19, are guided out of the proximal end 5 of the shaft in afirst conically widened portion of the housing 6 shown in FIG. 4 andextend as far as into the holding portion 7 arranged in the adjacentwidened and conical portion. The diameter of the—seen from across-sectional view—ring-shaped arrangement of the guided ropes 11 to11″″ and 13 to 13″″ increases from some millimeters, such as 3 mm in thearea of the shaft (provided that the shaft 1 has an outer diameter ofapproximately 5 to 6 mm) to approximately the double value. In thisarea, the ropes 11 to 11″″ and 13 to 13″″ may extend within guide means,too—such as rigid guide means 12 shown in dotted lines in the drawing—inspite of the fact that the holding portion 7 is fixedly arranged in thehousing 6, so as not to exert pulling forces only, but also pushingforces.

In its first portion adjacent the proximal end 5 of the shaft 1, thehousing 6 is widened correspondingly and is configured to be conical,for example. Next to this first portion, the housing 6 continues to forma widened spherical portion with the holding portion 7. In the firstportion, the guided ropes 11 to 11″″ and 13 to 13″″ are guided in arigid sleeve which is fixedly arranged in the housing.

In this holding portion 7, a fixing mechanism is located which is notshown in greater detail in the drawings and which can be operated by anoperating element, such as an operating lever 21, in order to releasethe proximal ends of the ropes 11 and 13 so as to be movable in theirlongitudinal direction or to fix them. A fixing device of this kind maybe configured as a guide plate arranged perpendicularly to the plane ofthe drawings, which contains holes with the corresponding geometry, e.g.circular, in one line or in two parallel rows in order to receive theropes 11 to 13 so as to be movable in the longitudinal direction. Ofcourse, the holes in the guide plate have a slightly larger innerdiameter than the outer diameter of the ropes 11 to 11″″and 13 to 13″″.In order to block or release the ropes in their longitudinal direction,a second guide plate which is configured to correspond to the firstguide plate and is arranged adjacent to it, and whose holes are alignedin the releasing position, can be displaced with respect to the firstplate via the operating lever 21, for example. In this case, the ropeends are clamped in their respective longitudinal position. Thus, theoperating lever 21 and the second guide plate, which acts as a clampingplate and can be displaced with respect to the first plate parallelthereto, provide a releasing and a locking position; in these positions,the operating lever and thus the clamping plate can be fixed via lockingmeans or can be pre-stressed permanently in a position, particularly thefixing position, by means of a spring, for example, so as to be put intothe releasing position only during the operation of the operating lever.At least in the portion in which they are capable of being displaced inthe longitudinal direction inside the fixing device, the rope ends maybe configured as rods or may be surrounded by rigid sleeves.Advantageously, this contributes to prevent deterioration or wear, suchas splicing of the ends as a result of continued use.

As will be apparent from FIG. 4, in the area of the partially sphericalsection which is located adjacent the conical first section of thehousing and which includes the holding element 7, an optical light guideis guided from inside the housing to the outside so as to be connectedto a light source which is not shown in the drawings. The cylindricalportion, which forms the proximal end of the housing and which has asmaller diameter than the spherical section, is configured as aneyepiece 8 (not shown in greater detail) for the operating personnel,such as the physician. This eyepiece 8 is connected with an opticalimage guide 25 which, like the optical light guide 23, extends insidethe endoscope to the distal end thereof.

At the distal end 3 of the endoscope or the shaft 1, there is anendoscope head 27, which is sealed off from the ambience like the entireshaft 1.

As will be apparent from FIG. 5, the endoscope head includes an imagelens 29 which is connected with the optical image guide 25 inside theshaft, and two light lenses 31 and 33, which are connected with theoptical light guide via a Y-connection in the interior of the shaft,which comprises a free space 10 (see FIG. 2) in the form of a channel,for example, in a manner which is not shown in greater detail.

As shown in FIG. 1, for reasons of stability, the leaf spring 9 issurrounded by an elastic net 35, which consists of steel braiding, forexample, and which is sheathed by a flexible sleeve 37 made of plasticmaterial or rubber. This sleeve 37 seals off the shaft 1 and, as thecase may be, also the head 27 from the ambience and, advantageously,reduces friction inside a tube or catheter at the same time.

As will be apparent from FIG. 1, the ropes 11 to 11″″ and 13 to 13″″guided in guide elements along an axis parallel to the longitudinal axisL terminate at their ends opposite to the proximal end at differentdistances from the proximal end. Their end points are fixedly connectedwith the corresponding guide elements, for example by laser welding, orthey have a larger head which projects from the corresponding guideelement in the distal direction and serves as a stop means to this guideelement in the proximal direction.

For reasons of clarity, only the ropes 11′, 11″ and 13″ as well as theirends 43, 41 and 39 are illustrated in FIG. 1. In the preferredembodiment shown in the drawing, the ropes are subdivided in pairs ofapproximately the same rope length, point-symmetrically or symmetricallywith the axis H, for example; the pairs of ropes (such as 11; 13, 11′;13′, 11″; 13″, 11′″; 13′″ and 11″″; 13″″) are fixed to the shaft 1 orthe leaf spring 9 at different distances from the proximal end 5 or forma stop means in the direction towards the proximal end 5, i.e. in thepulling direction of the ropes.

The different fixing points may subdivide the shaft into sections ofequal length; in the area which is likely to be subjected to strongbending forces by specific forms of use of the device, the distances mayadvantageously be chosen to be smaller in order to define the bendingaction more exactly. Contrasting to this, in parts which are likely toremain straight or parts in which no specific exact bending is desired,the distances may be made larger. As is apparent from FIG. 1, afterclamping or fixing the rope ends, stiffening of the last shape chosen inthe flexible condition will occur in the direction of fixing. Here, therope lengths of ropes 11 to 11″″ and 13 to 13″″ are fixed, and thus alsothe distances of the fixing points, i.e. the respective rope ends 39,41, 43 etc., from the distal end. Of course, the number of ropes and offixing points may be increased in order to keep the possible extensionor elongation between longitudinally adjacent fixing points within smalltolerances. Furthermore, in the arrangement in pairs, stability issupported not only by the pulling force, but also by the pushing forceof the respective partner of a traction rope. Moreover, the leaf spring9, too, has a certain tendency to subdivide the entire distance betweentwo adjacent fixing points in the longitudinal direction into equaldistances of adjacent turns or adjacent guide elements 19 in thelongitudinal direction in this area, if possible.

As, in the embodiment illustrated, the endoscope-type device is to beused for emergency intubation, an S-shape is to be obtained for anatomicreasons, for example, which has to be given to a flexible tube orcatheter which has previously been placed onto the shaft.

This S-shape is to be formed in one plane so that lateral forces can beexerted when introducing the device, too. To achieve this, in theembodiment, the lateral guide means 15 and 17 are not only connected tothe shaft 1 or the leaf spring 9 at their end points—contrasting to theguided ropes 11 to 11″″ and 13 to 13″″—, but at several, advantageouslyall points at which they contact the leaf spring 9 along thelongitudinal axis thereof. In this way, the opposite sides are neitherextendable nor compressible along these axes in their length, so bendingof the shaft 1 in the plane of the two lateral guide means 15 and 17,i.e. in a plane perpendicular to the plane of the drawing FIG. 1, isavoided.

After the pharynx has been opened with one hand using a laryngoscope,the shaft 1 with the tube is introduced into the lung via the tracheawith the other hand.

If the previously formed S-shape should prove to be not ideal whenintroducing the device, it is possible to change the stable shape byreleasing the fixing device using the operating lever 21 so that theportion which has already partially been introduced adjusts to thedifferent S-shape. In this shape which has been adjusted to the anatomicconditions of the individual case, the device can be further introduceduntil the physician detects via the eyepiece 8 that the entrance to thelung has been reached. Then, the rigid S-form of the endoscope ischanged by releasing the fixing device so that the endoscope, which isnow flexible, or the shaft 1 thereof can be pulled out of the tube.There are no or only very small frictional forces between the flexibletube and the shaft 1 so that inadvertent extraction of the tube isavoided.

The invention is not limited to endoscopy, particularly emergencyintubation, but may be applied to all endoscope-type devices. It ispointed out explicitly that this term is to be interpreted broadlyaccording to the invention; for example, bendable shafts in technologyrelating to tools, particularly for extending screw drivers, drills andthe like, and bendable links which are configured to be flexible orbendable at least in partial portions and in which stiffening to anarbitrary predetermined shape is desired, are to be included in thisdefinition. Advantageously, the formability and flexibility describedabove may exist along the entire shaft 1.

1. A device including: (a) a shaft having at least one flexible portionalong its length between a proximal end and a distal end; (b) at leasttwo longitudinally bendable pulling and/or pushing elements, the atleast two pulling and/or pushing elements each extending to the proximalend of the shaft and each acting on the shaft in an axial direction ofthe shaft at locations spaced apart from the proximal end of the shaftfurther than at least part of the at least one flexible portion; and (c)a fixing device located in a fixed position with respect to the shaftadjacent to the proximal end of the shaft, the fixing device having eachof the at least two pulling and/or pushing elements extending therethrough, and being adapted to reside alternatively in a releasingposition in which the pulling and/or pushing elements are unsecured tothe fixing device and are substantially free to move axially therethrough, or a locking position in which each pulling and/or pushingelement is fixed in place with respect to the fixing device.
 2. Thedevice of claim 1 wherein the shaft comprises a leaf spring having aring-shaped cross-section.
 3. The device of claim 1 wherein each pullingand/or pushing element comprises a rope which is substantially rigid inits longitudinal direction.
 4. The device of claim 1 wherein eachpulling and/or pushing element is received within a respective guideelement within the shaft so as to be slidable longitudinally withrespect to the respective guide element.
 5. The device of claim 1wherein the pulling and/or pushing elements are mounted in the shaft atan inner circumference of the shaft.
 6. The device of claim 1 whereineach pulling and/or pushing element acts upon the shaft in such a waythat it is limited to pulling and pushing directions for the respectivepulling and/or pushing element.
 7. The device of claim 1 furtherincluding two lateral guides extending longitudinally inside the shafton opposite sides thereof, each lateral guide being fixed to the shaftalong at least a portion of the length of the respective lateral guide.8. The device of claim 1 wherein the shaft includes an interiorlongitudinal channel.
 9. The device of claim 8 further including anoptical light guide or an optical image guide extending within thechannel.
 10. The device of claim 1 wherein the pulling and/or pushingelements are arranged in pairs with each pulling and/or pushing elementin a respective pair engaging the shaft in the axial direction atsubstantially the same distance from the proximal end of the shaft. 11.The device of claim 1 wherein the pulling and/or pushing elements arearranged symmetrically about the shaft.
 12. A device including: (a) ashaft having at least one flexible portion along its length between aproximal end and a distal end; (b) at least two longitudinally bendablepulling and/or pushing elements, the at least two pulling and/or pushingelements each extending to the proximal end of the shaft and each actingon the shaft in an axial direction of the shaft at locations spacedapart from the proximal end of the shaft; and (c) a fixing devicelocated at or adjacent to the proximal end of the shaft, the fixingdevice in a releasing position leaving the pulling and/or pushingelements unsecured to the fixing device so that the pulling and/orpushing elements are substantially free to move axially through thefixing device to enable the shaft to be bent to a desired shape, and thefixing device in a locking position locking the pulling and/or pushingelements in place with respect to the fixing device to retain the shaftin the desired shape.
 13. The device of claim 12 wherein the shaftcomprises a leaf spring having a ring-shaped cross-section.
 14. Thedevice of claim 12 wherein each pulling and/or pushing element isreceived within a respective guide element within the shaft so as to beslidable longitudinally with respect to the respective guide element.15. The device of claim 12 further including two lateral guidesextending longitudinally inside the shaft on opposite sides thereof,each lateral guide being fixed to the shaft along at least a portion ofthe length of the respective lateral guide.
 16. The device of claim 12wherein the shaft includes an interior longitudinal channel.
 17. Amethod for operating an endoscope-type device having a shaft with atleast one flexible portion along its length between a proximal end and adistal end and at least two longitudinally bendable pulling and/orpushing elements, the at least two pulling and/or pushing elements eachextending to the proximal end of the shaft and each acting on the shaftin an axial direction of the shaft at locations spaced apart from theproximal end of the shaft, the method including the steps of: (a)placing the at least two pulling and/or pushing elements in a conditionin which they are freely movable axially at the proximal end of theshaft and bending the shaft to a desired longitudinally bent shape; (b)with the shaft in the desired bent shape, placing the at least twopulling and/or pushing elements in a condition in which they are in afixed position prevented from moving axially at the proximal end of theshaft to fix the shaft in the desired bent shape; (c) inserting theshaft into an inserted position in an orifice while the at least twopulling and/or pushing elements are in the fixed position fixing theshaft in the desired bent shape; (d) with the shaft in the insertedposition, placing the at least two pulling and/or pushing elements inthe condition in which they are freely movable axially at the proximalend of the shaft; and (e) moving the shaft from the inserted position inthe orifice while the at least two pulling and/or pushing elements arein the condition in which they are freely movable axially at theproximal end of the shaft.
 18. The method of claim 17 wherein the stepof moving the shaft from the inserted position in the orifice includesadjusting the position of the shaft to a different bent shape andfurther including the steps of: (a) again placing the at least twopulling and/or pushing elements in the condition in which they areprevented from moving axially at the proximal end of the shaft to fixthe shaft in the different bent shape; (b) adjusting the position of theshaft in the orifice to an adjusted position; (c) again placing the atleast two pulling and/or pushing elements in the condition in which theyarc freely movable axially at the proximal end of the shaft; and (d)entirely withdrawing the shaft from the orifice while the at least twopulling and/or pushing elements are in the condition in which they arefreely movable axially at the proximal end of the shaft.